Pons, Carolina Galindo, Josué M. Martín, Juan Carlos Torres-Moya, Iván Merino, Sonia Herrero, María Antonia Vázquez, Ester Prieto, Pilar Vallés, Juan Antonio Guiding losses estimation in hydrogel-based waveguides J. Phys.: Conf. Ser. 10.1088/1742-6596/2407/1/012032 2022 2022